Measured-service automatic telephone-exchange system.



Wl W. LEAUH.

MEASURED SERVICE AUTOMATIC TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED 0G'1.15,1906.

931,132. Patented Aug. 17, 1909.

2 SHEETSSHEET 1.

w. LEAGH. MEASURED SEE-VICE AUTOMATIC TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED 00T.15,1906.

93 1 1 32. Patented Aug. 1?, 190's.

2 SHEETS-SHEET 2.

w 50:65 waaea:

. 7/z1/e 7660 r:

stop 8 may form the member-of a pair 01' I contacts 8, 9 adapted to beclosed by the coin,

.Stood,. that 'other forms of coin collectors energized applies currentfrom a generator 20 11 of the coin collector at the station of vsuchline, to cause said magnet to tilt its grounded mechanism and theapplication of a busy example, positive current. to the limb l of thecalling line, operating magnet 11 of the tilt'its armature 13 inadire'ction to remove so" 16. leading to the outside of the box. The

controlled from the calling station A. At

lector C, of a well-known type, having a line switching mechanism.

I tors a b was completed, and in addition to central office byconductors a Z and line switching mechanism of any desired type i thecalling station is provided a coin colpolarized magiietll in a branch 12from the limb 1 of the line to earth, said magnet being unresponsive tothe battery at the central office. The said magnet is provided with atilting armature 15 carrying a pair of stops '15, 8, adapted to supporta coin tentatively deposited in the collector; the

and which may control. the operation of the The armature 13, when tiltedin one direction, is adapted to Withdraw the stop 15 from the path of'the coin and allow the same to fall into a refund chute 16 leading tothe outside of the coin collector; and when the armature is tilted inthe opposite direction, it removes the stop 8 from the path of ,the coinand ermits said coin to fall into chute 17 eading to a cash box 18. Itwill be underthan the one shown may be equally as well employed inconnection with my invention.

At the central oifice is provided a relay 19 Which receives current whenthe called subscriber removes his telephone from its hook in response toa call; said relay when of, for example, negative current, 'to the limbl of the calling hue and operates the magnet armature 13 in a directionto remove the stop .8 from the path of the coin, and permit said coin tofall into the chute leading to the cash box. The armature 21. of relay19 is connected with a conductor 22 leading to the limb l of the callingline, and said armature may carry a spring member adap ted to make amomentary wiping contact with a movable contact connected with aconductor 23 leading'to the free pole of a enerator 20. In case thecalled line were usy, a test relay 69 would operate before thecontinuity of the conduccausing the restoration of the switching test tothe calling line, would serve to apply current from a grounded generatorof, for

coin collector, and causing said magnet to the stop 15 from the path ofthe coin and permit the coin to fall into iherct'und chute free pole ofa grounded generator is connected Wlth a conductor 25 which leadsthrough the armature 26 and normally-open front contacts of said testrelay to the back contact of the armature 21 of relay 19. Thus when thetest relay 69 is operated due to the busy condition of the called line,the armature 2(5 of said rclayin its attractive movement permits currentto flow from the generator 2% over conductor 25,'armature 21 and backcontact of relay 19, conductor- 22 to the limb l of the line and toearth through the magnet of the coin collector at the calling station.

The magnet 27 is adapted to be included in the ringing circuit and torespond to the ringing current therein, to eliect the connection of thegenerator 2% with the limb 1 ot the line to operate the magnet 11 andrefund the coin. The magnet 27 is adapted in response to the ringingcurrcnt passing therethrough, to make and break a circuit- 28 includinga source of current and the stepping and retaining magnets-of a gear29adapted through the agency of intermediate reduction gearing toadvance a .disk 30 carrying a cam 31 adapted when the disk has beenadvanced a predetermined distance, 90 dependent upon the time it isdesired to give the called subscriber 'in whichtoanswer the call, toclose a pair of contact springs 32, 33, and complete a branch 23 1around the armature 2(3 and its front contact of relay 69. 5 Currentmay, now flow from the generator 24- by way of conductors 3 1, 25 and 22to limb l of the line, to operate-the coin collector magnet and refundthe coin. Said cam 31 may also a pair of contacts 35 m adapted tocomplete the continuity of a con ductor 36 leading from a special signalapparatus 37 to the limb 1 of thecalhng line, this'si'gnal indicating to.the calling sub scriber that the called party has failed to respond.The cam 31 may also when ad vanced the said predetermined distance,effect the restoration of the line switching mechanism; said cam mayopen a pair'ot' contacts controlling .the circuits of the, re- 11otaining mechanism.

Turning now to Fig. 1, I will describe in detail a telephone. exchangesystem equipped with improvements embodying my said invention. In saidfigure, two telephone lines are shown extending in limbs l, Zfromsubstations A, B, respectively, to a central oflice, where each line isprovided with line selecting and crn necling mechanism. I will describein detail the circuits and apparati'ls 12o associated with the line ofstation A,'it

being understood that the line of station B is equipped in exactly thesame manner; and

for convenience ()tdesc1'ipti( i1.I will con;

sider station A as the calling station andstation ll as the calledstation. r

At the substation is provided the usual .telephone apparatus in a bridgeof the limbs 1 2. A. calling device 3 is provided at the substation,which may comprise a springwith a set o th EIOSIALUH opposite the dtermini nctntited arm ladapted to be set in a posi tion representin thenumber of the line wanted, or a d t thereolf, and to be retnrned underthe influence ot' a spring to operate a'gear I) to cause the same tointermittently close a pair cl contacts c 7, a number of times dependentupon the adjustment of the arm l. The arm 4 while away from normalposition maintains open a pair of contact springs controlling thesubstation bridge of the line.

The contacts 6, 7 control tlieoperation of the central oliice lineselecting mechanism, these contacts being in turn controlled by a pairof normally-open contacts 8, 9, within the coin collector U, which areclosed by a coin when tentatively deposited by a subscriber. The contactspring 7 is connected to earth, and the contact spring is con nectedwith a conductor ll) which leads throu 'h contacts 8, 9, within thecollector, to the limb ot'. the line.

it: the central office, the limbs l 2 of the hi0 m y-pass through thearniatures c 0, respectively, of a cubotl relay (1, to the con- .cts134, 3."), upon the rotatable selector arm iinb 2 extending; through aconno, the l denser, at nature 37 and its norm front contact of relay38, through. the armature 39 and back contact of relay at), to the.selector contact 5135, while the limb 1 extends through a condenser,armature 41 and back contact of relay 40, to the conact 34-.

The third. terminal 412 upon the selector arm is connected with aconductor 4-3 lead- .i through the winding of relay 38 to ground, Saidrelay 38 beingpreferably gish in its action, The contact arin so "m redto sweep orcr terminals, which my be connected directly with telephonenes, or with trunk lines leading to other selectingrl'ilt'it'lltll'llhlll. in the present case, for convenience o'l' tiesription and i lustration. l have shown thrltt'illlllftlS asrepresenting: telephone lines. that is, each line is provided threeterminals, tern'iinal i -l being; connected with the limb 1 ol the line,while the tc h the ally-open mail to is connected w t limb 2 oi the meThe local terminal 4-6 oi h s t connected with the conductor 7,

ich leads through the cut-oil" relay w to the rec pole or grouruledbattery ltv. The limbs are, of course, multiplied to contacts upon thedifferent selectors S in the eX- change.

Tl lcctor arm 36 may be mounted upon l rotary shaft 49 provided with lapled to be engaged by a stcp- Til operated by an clcctrotnannet ratchetl t-inn" provided. with a rer by a n'iugi'iet i li n ha; been moved to,esired Pet of line a magnet 55 is arranged to force selector 1 l I l l ll l l l l the shaft ll) downwardly and bringthe con lacls upon theselector arm into engagement \Yllll the desired line terminals.

Jr relay 5b, which controls the 1 ing mechanism, in prox'ided in abridge of the limbs l 2 of the line, said bridge also including" abattery 56, having its negative pale grounded, and a relay 50, saidbattery being interposed between the relays it; ill), with its; positiveor tree pole connected with the limb 2 of the line. lrhcn the telephoneis'rcmovcd from its hook t the calling station A, a circuit is completedby way ol the bridge 57 and limbs 12 for the relays Mi iii), and currentalso tlows from the tree pole of battery 58 through bridge 57, limb 2 olthe line, through the snbstation bridge closed by the telephone switchso, to limb l of the line, and thence to earth through branch 12.

inc selcetwhich includes the elcctromagnet oi the coin ,ture of thestorming magnet n its up collector. The airrent from the said centralotlice battery does not all cct the magnet ll of the coin collector,

The relay 5:6 provided with a si a mature (31, which is adapted when ited to close a shunt (32 about the cut-oil relay (l of the calling line,,to pit-rent. its improper actuation if such line should be n' lectedand tested by another line during; the conversation.

Linc selecting operation.-"he armature (53 of relay 56 controls thecircuits of the line selecting mechanism, the armature being connectedwith the coi'iductor (i l, which extends to the :lrce pole oi? battery5R, while the front contact of said armature is connected with aconductor or, which leads thronrh the retaining magnet 54 and steppingmagnet F2 in series, hrou 'h normally closed contacts so ()7 controlledby relay 5: through the aianature as and back contact of busy test relay(if), to earll A branch con doctor TO leada from conductor throu h thewinding oi eonncrting magnet air, through a pair of contacts [1, whichare intermittcntly made and ln'oken by the arma oration, back to theconductor of). F uid coularls T1 are arranged to prevent, while beingrapidly made and broken. the cnergizalion of the connecting nnigrnct 55,but when allowed to come to rest to permit vqullicient current to flowto operate the magnet 55. Tl-hc ma 55h provided with an armature T52connected by a conductor 73 with the said conductor 7J0. :t w'aidarmature, when attracted, forces; the shalt 4-9 downwardly, and engagesspring (37 to separate the same tron: its an il 66, to thereby completea circuit for magnet 55'independent of the contacts 71. inn subscriberat station A, call, deposits a coinin the collector which falls illponthe stops l5 ,8, closing the contacts 8 9. He thereupon operates thecalling tlevice to make and break the contacts 6 7 a lhe call-, 7 1nmutating 'a l. l. O

predetermined number of times, dependent upon the number of the linedesired, and a circuit, is intermittently made and broken for the relay56 at the central office, said circuit extending from the free pole ofbattery 58, through relay 56, bridgt 7, limb 2 of the line, contacts 8 9clos'. by the coin, through the contacts 6 7 of the calling device.Relay 56, in vibratinggi't s armature 63', iinierinittently makes andbreaks a circuit extending from the free pole of battery 58, conductors64 and 65, through retaining magnet 5st, and stepping magnet 52, throughthe springs 66 67, armature 6S and back contact of busy test relay 69 toearth. The re- 1 taining magnet 54 is operated to throw the' pawl intoengagement with the ratchet 50, and also the stepping magnet 52 operatesto rotate the shaft 49 and bring the select-or arm into positionopposite or over the' set of terminals representing the line desired.

lVhen the'contact arm 4 of the calling device returnsto normal position,after operating contacts 6 7, it closes" again the metallic circuitofthe limbs l 2, maintaining the relays 56 59 energized, and currentflows from the tree pole of grounded battery 58through conductors 64- 6570, through connecting magnet 55, contacts 71, which are now at rest,back to .conductor 65 and thence to earth through the armature 68 andback contact of relay 69. Sufficient current now flows in this circuitto operate the connecting magnet which attracts its armature 172,forcing the sl'ia't't L9 downwardly, and bringing the terminals 3% 354.2 into engagemcnt with the terminals 45 44' 46 representing the calledline. The armature 72 also engages contact spring 67, to separate thesame from its anvil 66, and completes'a circuit :trom conductor 65through the connecting magnet 55, conductor 70, conductor 73,

armature 72 of relay 55, and contact spring 67, back to conductor 65,and to earth independent of the contacts 71.

Test of called lim -'llheiimb 2 of the line is normally open at thearmature 37 and front contact 0 t sluggish relay 38, which is includedin the circuit above traced, and a testing conductor extendst'rom theter-- minal 35 upon the selector arm, through the limb 2 of the line, tothe armature 37 of relay 33. whose had: contact 1s connected with aconductor 74 leading through a winding 75 of the busy test relay toearth. In case the called line is busy there will be potential upon theterminal 44 from the central otfice battery 58uby way of the substationof the line, and current will flow through the testing conductor andwinding of the test relay 69 to earth and energiie said'relaybefore thesluggish relay 38 has had time to respond to the current in the localcir uit 47 43, The relay 68 when thus energize attracts its armature 68,opening the circuit 64 65-5 70-73-65 of the connecting magnet 55, andallowing'the selector mechanism to be restored to normal condition bymeans of a suitable spring. ",Said relay 69 is also providedwithan"a"rmature 76, which is connected with a conductor 77 leading to thefront contact of an armature 78 of relay 56,

said armature 78 being connected with the their initial attractivemovement, current flows from the free pole of grounded battery 82through the winding of said relay, armature 78 and front contact of saidrelay 56 to limb l of the line, and thenceby way of bridge 57 to earth,locking up the relay 69, whereupon busy test current is applied to'theline, said current flowing from the secondary winding in conductor 7 9,throu h conductor 77, limb 1 of the line, through tie substationapparatus, limb 2 of the line, bridge 57, to earth. The subscriber, uponhearing the busy tone in his telephone, hangs up his receiver 56, whichretracts its armatures, the armature 7 8. opening the locking circuit ofthe busy tone relay 69 and restoring the same to normal position.

, Refund of 002% where called partys line is bus3 .-The relay 69, whichoperates when the called line is busy, .is provided with an armature 26,adapted when attracted to complete the connection of positive genera,-tor 24: with the limb 1 of the line, by way of conductors 25, 22.Current from the positive generator 24 now flows to'ear'th through thewinding of the electromagnet 11 of the coin collector, operating thestud magnet and causing the same to tilt its armature 13 in a directionto throw the coin into the refund chute 16.

(J'alla'ag a free Zinc w/zere subscriber (mswcra-lrtthe presentcondition, when the contacts upon the selector rest in engagement withthe terminals of the called line, there is and cuts off the conductor 74, which includes the winding 75 of the test relay, from the limb 2ot'the line, at the same time complet ing the continuity of said limb.The relay 38 is provided with an arnmture 83 which is connected toground, the front contact of said armature being connected with aconductor 8% which leads through the relay 4:0 to the free pole of-agrounded battery 85, and said relay 38, when attracted, in case the ductcalled line in free, ceinpletes r circuit to p crate relay 20, whichthcreu 'mn attracts i'ls arn ur 1 31 -fl-l., wh. t' l c -utaci's turnthe terminals cl conductor :3 including u. ringing generator 87 and thew ling 88 0f a relay an. 'lfh w, when the y l-t is en ,cd. ringing cirent flex iron] the upper pole, for example. of the generator T throughthe armature ll and front cci ol re ll line conductor l cnnia 1 upcn tncselector; liinb 2 cl? ihe callc thencc throng h the hell at t 1substation of the L'Zlllill line, back over limb l at the called line,thrcugh the cunt ts H cf the hector. liinb 1 cl thc calling line arniatn39 and front cnntzwt of relay ell), through the windin $8 cl? the i iSf), in the lower pole of lhc cnc'alor The relay is arranged to la unrnneivc to the current llowing in the circuit just traced, owiir the high1' Itancc in the line at the sub tiun, l 1 l ilic called sulb ,riberrespon c. by renamin his telephone trein its heck, a shunt isestablished about the ln'i containing the bell and condenser at thesub-- ergize ihc in" its arriaturi arniaturc fltl nil net 89 sutlicie inattract y le iii-(int contact 0i. relay 89 in included in; a con- .llwhich leads from ihc free pole of {,{ltlililnttl miter lhruugh a lbw rccn e '.\'i-' ling 9; cl rel FM, while the urinalure fi l! l. L =nncctcd1th a cmuluclor h which lcudu threw ac armature ill and ..i tn thebridge 57- lrnnl. contact c-l' clay and earth. The conductors ill, 93and 57 act as a shunt abcut relay L0, to czluere the same to retract itsarniiiturcs 39, 4- and break the rii ing circuit above t 'acedl therilay 55f being; ed up by me f winding J9,

included in said shurn 1g circuit. A bridge 535 of the limbs l" 2 (Ifthe line is provided between the condensers and the contacts upon theselector. said bridge containing a 3 impedan e coils to fur-- Jill-llthe talhing "l'l'tlliT required by the called v talicn for iranz-zuiisri n purpnsen. 'lhc al'nnilul'c ill of relay S9 is connected bycnnductcr .22 with linib l of the calling; line, and l'w' adapted inattracting tn ccinplelc n10- ccn between a pair of wiping CUllLdC lS tncuni'icct the coxuliurtcr 23 including grounded n ative generator 20with conductor :22 and limb L A momentary inipulse 0i current from midgenerator new flows tn earth through il e magnet ll of the cuin'collector, uperatin said ma mauve the same in till i fully f0 HH "l'/'in; circuit in ii cpcratcs lhc in anian and ung inc d usually are, oneand the e I a: answer e ici its )i' 1 these i an Sznnc.

t will be lllitltfin'iOUtl, that while *lcr c0nicnce of illustratinn anddescription, I have shown an clnbcdinient cl my invention applied to :1small system, the inrcntien may be cqu applicable to many cihcr wctezns,hnili lar and Hun-ill; and l do not deche to y be 11 i need an limitingthe application of my inrcntinn to any particular antoniai-ic i'clcphuncexchange i 'liein.

che coinhinatien with a, calling and 21 called tclej'ihcnc lineextending from sub nil (0113 to a central ntl'ice, of a coin ccllecturis at the n. station of the calling line ha ing a coin cnnlmllcd magnetcnnneclcd with and line, automatic line switching niccluinisi'n in saidcullcclnr, 'l ur unilin mid linen, gcncralnr at the central nil" Foroperating said mail-Such a stance of riu 'ing current, incurs autonitically operated upon the conncctmn of 51 lines for applying said ringing current to the called linc a relay in said ringing circuitunresponsive to said current while lhc normal high rcsi'tance isincluded in the called line at {he etatinn thereof. said Mela-3'rcspnnrjling when 5 id resistance is shuntml by ihc rcium'al (it theralled subscribcrs tclcphnnc. and means controlled by 1 said relay lnrcnnnccling' anid gcucratnr with 'llu called line.

2. The cnnibiuaiimi with a calling and a mulled telephone line extendinglrnui nub stations te a ccnt ml zil'licm at a will collcc'tor at tlu;-:ub-:t the culling line having a min cmilrol c l n 'ccenncctcd withsaid line automatic line switching; mechanism upon lh'c tentativedeposit cl a coin in said ccitector, l m uniting said lines, a generatorat the central nllicc for up; 'atii'ig said nuvmct a lOillCt. cl ringingcurrent, inc-ans antmnal r l; nperaled upon the mnncctiun nl rid lllliln*lur a; plying said ringing currcni in the called lino a relay in saidringing; rircnil unresponsive tn Silltl current while the nurnial highresistance is included in thc called line at, lhc rslatinn til cruel,vaaid rclar r spending when uaid ,uhuntcd out by the l'LHH/Vill cl lliccalled l we rabl npcu the tentative deposit 01' a cuin subscriberstelephone, means controlled by ,said relay for connecting said generatorwith The combination with a callingand a.

called telephone line extending from substations to a central office, ofa coin collector atthe substation of the calling line having a coincontrolled magnet connected with said line, automatic line switchingmechanism operable upon the tentative deposit of a coin in saidcollector, for uniting said lines, a generator at the central oflice foroperating paid magnet, a source of ringing current, means automaticallyoperated upon the connection of said lines for applying said ringingcurrent to the called line, a relay in said ringing circuit unresponsiveto said ringing current while the normal high resistance is included inthe called line at the station thereof, said relay responding when saidresistance is shunted out by the removal of the called subscriberstelephone, and a pair of wiping contacts operated by said relay inresponding to connect said generator momentarily with the calling line.

Jr. The combination with a calling and a called telephone line, of acoin collector associated with the calling line at the station thereof,automatic line switching mechanism, operable upon the tentative depositof a coin in said collector, for completing the connection of saidlines, and means automatically operated in case said line is busy, foroperating said coin collector to refund said coin.

5. The combination with a calling and it called telephone line, of acoin collector associated with the calling line at the station thereof,automatic line switching mechanism, operable from the calling station,upon the tentative deposit of a coin in said collector, for connectingsaid lines, a test relay operated in case the called line is busy, andmeans controlled by said relay for operating said coin collector torefund said coin.

G. The combination with a calling and a called telephone line, of a'coincollector at thecalling station having a coin-distributing magnetconnected with the line, automatic line switching mechanism, operablefrom the calling station upon the tentative deposit of a, coin in saidcollector, for connecting said lines, a test relay, a circuit thereforcompleted in case the called line is busy, a source of current adaptedto operate said magnet to refund said coin, and means controlled by saidtest relay for connecting said source of current with said calling line.

7. The combination with a calling and a called telephone line extendingfrom substations to a central office, of a coin collector at. thecalling station, automatic line switching mechanism at the centraloflice, operable from the calling station upon the tentative deposit ofa coin in said collector, for uniting said lines, a busy signalapparatus auto matically applied to the calling line in case the calledline is busy, and means controlled by said busy signal apparatus inoperating, adapted to actuate said coin collector and refund said coin.

S. The combination with a calling and it called telephone line extendingfrom sub stations to a central OlllCB, of a coin collector,

at the calling station, automatic line switching mechan sm at thecentral otlice, operable from the calling station upon the tentativedeposit of a coin in said collector, for unit ing said lines, a busysignal apparatus automatically applied to the calling line in case.

the called line is busy, and means controlled by said busy signalapparatus in operating, adapted to actuate said coin collector nd refundsaid coin, and means controlled by said busy signal apparatus, forresfiorin said line switching mechanism to norma condition.

t). The combination with a calling and a called telephone line extendingfrom substations to a central otlice, of a coin .collector at thecalling station having a polarized coindistributing magnet.- connectedwith the line, autoi'natic line switching mechanism,- oper; able fromthe calling station upon the tentative deposit of a coin in saidcollector, for connecting said lines, sources of current of oppositepolarity at the central ofiice, means, automatically operated in casethe called subscriber answers, for connectingone of said sources withthe calling line to operate said magnet and finally deposit said coin,and means, automatically operated in case the called subscribers line isbusy, for connecting said other source of current with the calling lineto operate said magnet and refund said coin.

10. The combination with a calling and :1 called telephone lineextending from substations to a central office, of a coin collector atthe calling station having a polarized coin-distributing magnetconnected with the line, automatic line switching mechanism,

operable from the calling station upon the tentative deposit of a coinin said collector, for connecting said lines, sources of current ofopposite polarity at the central'oifice, a

called telephone line, of a toll device associated with the calling lineat the substation there-of, automatic line switching mechanism, operableupon the tentative actuation of said toll device, for completing theconnec tion of said lines, and means, automatically operated, in casethe called subscriber fails to respond to the call,.l'or restoring saidtoll device to norm condition Without placing said calling party toexpense.

12. The combination with a calling and a called telephone line extendingfrom substations to a central ollice, of a toll device associated withthe ailing line at the substation thereof, tltltOlIltllfiC lineswitching mechanism, operable upon the tentative actuation of said tolldevice, for completing the connection of said lines, means,automatically operated, in case the called subscriber fails to respondto the call, for restoring said toll device to nor mal condition Withoutplacing said calling partly to expense, and means automatically operatedupon the response of the called subscriber for operating said tolldevice to place the calling subscriber at expense.

The combination With a calling and a called telephone line extendingfromsubstations to a central ol lice, of a toll device associated with thecalling line at the substation thcreoit', automatic line switchingmechanism, operable upon the tentative actuation of said toll device,for completing the connection of said lines, means, automaticallyoperated, in case the called subscriber fails to respond to the all, forrestoring said toll device to normal condition Without placing the saidcalling party to expense, and means, automatically-operated upon theresponse of the called subscriber, for operating said toll device toplace the calling subscriber at expense, and means,autoinatically-actuated in case the called line is busy, for' operatingsaid toll device without placing said calling subscriber to expense.

1%. The combination with a calling and. a called telephone lineextending from substations to a central oltice, of a coin collector atthe substation of the calling line, automatic line switching mechanism,operable upon the tentative deposit of a coin in said collector,

tor cim'ipleting the connection of said lines,

and means, automatically operated in case the called subscriber fails torespond alter a predetermined period, for operating said coin collectorto refund said coin.

15. T he combination with a calling and a called telephone lineextending from substations to a central otiicc, ot' a coin collector atthe substation ot' the calling line, automatic lino switching mechanism,operable upon the tentative deposit of a coin in said collector, forcompleting the connection of said lines, means tor automaticallyapplying ringing current to the called line upon the complel l i l l l ll i l l l i l i i l l l l l lion ot'conncction therewith, and means,antomatically operated, in case the called subscriber tails to respondafter said ringing current is applied apredeicrinined period, foroperating said coin collector to refund said coin.

16. The (fOi'lilJilllit'lOll with a calling and a called telephone lineextending from sul'istations to a central ollicc, of a coin collector atthe substation oil the called line, automatic line switching mechanism,operable upon the tentative deposit of a coin in said collector, forcompleting the connection of said lines, means for applying ringingcurrent to the called line, stepping mechanism operated by said ringingcurrent, and means ope 'ated by said stopping mechanism after aproduct'- mined period, for operating said coin collector to refund saidcoin.

l7. The combinationwith a calling and a called telephone line extendingfrom substz tions to a central oilice, of a coin collector at thecalling station having a coin-distributing magnet connected with theline, automatic line switching mechanism, operable from the callingstation, upon the tentative deposit ofa coin in said collector, forconnecting said lines, a source of current at the central otlice adaptedto operate said magnetto refund said coin. and means, automaticallyoperated in case the called subscriber fails to respond, for connectingsaid the calling line.

l8. The combination with a calling and a called telephone line extendingfrom substations to a central otllce, of a coin collector at the callingstation having a coin-distributing magnet connected with the line,automatic line switching mechanism, operable from the calling station,upon the tentative deposit of a coin in said collector for connectingsaid lines, a source of current at the central oilice adapted to operatesaid magnet to refund said coin, means for applying ringing current tothe called line, a relay in said ringing circuit, and means operated bysaid relay alter the called subscriber has been rung a predeterminedpeli iod and fails to answer, adapted to connect said source of currentu'ith the calling line.

19. The combination with a calling and a called telephone line extendingfrom su ations to a central olllcc, of a coin collector at the callingstation having a coin-distributing magnet connected with the line,automatic line switching mechanism, operable from the calling station,upon the tentative deposit of a coin in said collector, for connectingsaid lines, a source ot. current at the central ofiicc adapted tooperate said magnet to refund said coin, means for applying ri-ngingcurv rent to the called line, a relay in said ringing circuit responsiveto said ringing current, and electromagnetic stepping mechanism onsource of current with erated by said relay, said mechanism beingadapted when ringing current has been applied to the called line apredetermined period, to connect s aid source of current with thecalling line.

Q0. The combination with a calling and a *alled telephone line extendingfrom substations to a central office, of a coin collector at the callingstation having a coin-distributing magnet connected with the line,automatic line switching mechanism, operable from the calling station,upon the tentative deposit of a coin in said collector, for connectingsaid lines, a source of current at the central office adapted to operatesaid magnet to refund said coin, means for automatically applyingringing current to the called line upon the completion of connectiontherewith, a relay in said ringing circuit, a circuit closing device,stepping mechanism therefor, operating magnets for said mechanism, acircuit for said magnets intermittently made and broken by said relay,and a connection of the said source with the calling line completed bysaid circuit closing device when advanced a predetermined distance.

21. The combination with a calling and a called telephone line, of atoll device associ- .ated with the calling line at the substationthereof, automatic line switching mechanism, operable upon the tentativeactuation of said toll device, for completing the connection of saidlines, and means, automatically operated, in case the called subscriberfails to respond to the call, for restoring said toll device to normalcondition without placing said calling party to expense, and acharacteristic signal applied to the calling line in case said calledparty fails to respond.

22. The combination with a calling and a called telephone line, oi? atoll device associated with the calling line at the substation thereof,automatic line switching mechanism, operable upon the tentativeactuation of said tolldevice, for completing the connection of saidlines, and means automatically operated, in case the called subscriberfails to respond to the call for restoring said toll device to normalcondition without placing said calling party to expense, and meansactuated upon, the failure of said called party to respond, forrestoring said switching mechanism to normal condition.

23. The combination with a calling and a called telephone line extendingfrom substations to a central office, of a coin collector at thesubstation of the calling line, a coindistrilouting magnet for said coincollector connected with the calling line, automatic line switchingmechanism at the central oilicc for completing connection between saidlines, means at the central oflice for actuating said "coin collectormagnet to deposit a coin tentatively. deposited therein, and means atsaid central oilice for actuating said magnet to refund said coin.

it. The combination with a calling and a called telephone lineextcndii'ig from substations to a central ollice, ot a. coin collectorat the substation of the calling line. a polarized coin-distributingelcctromagnct for said coin-collector connected with the 'alling line.automatic line switching mechanism at the central ol'lice for completingthe connection of said lines, sources of current at the central olliceof opposite polarity, means at the central ()l'lltit' 'i'or applyingcurrent from one of said sources to the calling line to actuate saidmagnet and deposit a coin tentatively deposited in said collector, andmeans at said central oitice for applying current from said other sourceto the calling line to actuate said magnet and refund said coin.

25. The combination with a calling and a called telephone line extendingfrom substations to a central otlicc, ot a coin collector at thesubstation of the calling line, a coindistributing electromagnet forsaid collector connected with the calling line, automatic line switchingl'nechanism at the central ollice, operable upon the tentative depositof ,a coin in said collector, for completing connection between saidlines, means at the central oliice for actuating said magnet, in casethe called party responds, to deposit said coin, and means at saidcentral ol'lice for actuating said magnet, in case connection cannot behad with the called party, to refund said coin.

iii. The combination with a calling and a called telephone lineextending from substations to a central ollicc, oi a coin collector atthe substation ot the calling line, a coindistributing electromagnet forsaid collector connected with the calling line, automatic line switchingmechanism at the central ofiice, operable upon the tentative deposit ofa coin in said collector, for completing connection between said lines,means at the central otlice tor actuating said magnet, in case thecalled party responds, to deposit said coin, and mechanism at saidcentral oliice, autonuitically operated in case the called party failsto answer, or his line is busy, for actuating said magnet to refund saidcoin.

27. The combination with a calling and a called telephone line extendingfrom substations to a central ollice, of a coin collector at thesubstation o the calling line, a polarized coin distributingclectromagnet for said coin collector connected .wilh the calling line,automatic line switching mechanism at the central oliicc for completingconnections between said line utter the tentative deposit of a coin insaid collector, sources of current of opposite polarity at the cent 'alollice, au-

tomatic mechanism at the central otlice, operscrlber,

for applying curent from one of means for applying current from saidother source to the calling line to actua'iia magnet and refund saidcoin.

In witness whe eo'f, EI hal e-unto subscribe my name this 13th (lay ofOctober 1 D,

